Recently, IC cards and mobile telephones are required to be thinner, smaller, and lighter in weight. For the sake of satisfying this requirement, semiconductor chips to be incorporated into such devices also need to be thin semiconductor chips. Specifically, as the thickness (the film thickness) of a semiconductor wafer that is used as a base of a next-generation semiconductor chip, a thickness in a range of 25 μm to 50 μm is said to be necessary whereas the thickness of a semiconductor wafer that is used as a base of a conventional semiconductor chip is in a range of 125 μm to 150 μm.
Methods for obtaining such a thin semiconductor wafer include a method in which, in order to maintain the strength of a thinned semiconductor wafer, a supporting plate for supporting the thinned semiconductor wafer is attached thereto. In this method, first, a semiconductor wafer and a board such as the supporting plate are bonded to each other by (i) a tape having an adhesion layer on both sides or (ii) adhesive. Second, the semiconductor wafer supported by the supporting plate is grinded with a grinder etc. A thinned semiconductor wafer is thus made. Lastly, the supporting plate is stripped off from the thinned semiconductor wafer.
In stripping the supporting plate, an adhesive substance of adhesion layers of the tape or an adhesive substance of the adhesive, which tape or adhesive fixes the semiconductor wafer and the supporting plate to each other, would remain on the semiconductor wafer. Therefore, it is necessary to perform a treatment for removing the remaining adhesive substance from a surface of the semiconductor wafer that surface is in contact with the supporting plate, so as to clean the surface.
The removal of the remaining adhesive substance can be performed by a method such as (i) spin cleaning in which a cleaning solution is spread over the surface of the semiconductor wafer by spinning the semiconductor wafer, and (ii) immersion cleaning in which the semiconductor wafer is immersed as it is in the cleaning solution.
There is an example in which a mechanism similar to that of the spin cleaning is applied to a development apparatus. Japanese Unexamined Patent Publication 2004-274028 (Tokukai 2004-274028, Publication date: Sep. 30, 2004) discloses the development apparatus that applies a photoresist to a substrate, transfers a circuit pattern to the photoresist by use of a photolithographic technique, and supplies a developing solution with a surface on which a latent image pattern is formed, thereby developing the applied photoresist film. As a mechanism for supplying the developing solution onto the photoresist, the spin method is employed for the development apparatus.